Mind-Body Problem: The difficulty of explaining how the mental activities of human beings relate to their living physical organisms. Historically, the most commonly accepted solutions have included mind-body dualism (Descartes), reductive materialism (Hobbes) or idealism (Berkeley), and the double aspect theory (Spinoza).

Although many contemporary philosophers accept some form of identity theory, they often rely on behavioral or functional methods of analyzing mental events and upon the achievements of neuroscience.1